"Dear orthopedic doctors", explain to me, in what science is it described that the use of insoles and corsets is an effective therapy for posture problems?
The question is of course rhetorical, I know that in response I will hear some kind of inarticulate mumbling, and the especially gifted will send me links to studies that they did not understand, or that were done crookedly 
Let me take a moment to explain the harm of this "therapy". And I'll start with the basics - how the peripheral nervous system controls muscles. This is physiology. What you missed or didn't understand in honey 
So, there is a brain, there is a spinal cord, there are peripheral nerves. The brain decides to do something, for example, bend the arm, an action potential arises in the brain, this is a nerve impulse, which is transmitted as if by relay to the necessary section of the spinal cord, and from it, through motor neurons ( motor function) , the signal goes to the peripheral nerves of the arm (for example, the radial nerve). As soon as the action potential reaches the biceps of the arm, it contracts, BUT for the correct functioning of the body this is not enough.
There must be feedback with the brain, roughly speaking, to understand that the command "bend the arm" is performed by the right muscles, for this the sensory function of the nerves is needed. All kinds of mechanosensitive and other receptors receive information about muscle contraction, fascia tension, etc. and transmit this information back to the brain. The point here is this: if a motor or sensory function is impaired, the brain does not receive enough information about the work of the required muscle and turns on other muscles in this area to compensate for the function of the muscle that did not carry out its "order". I already wrote about this in the post about flat feet. For some reason, doctors have not understood this point.
Now, closer to practice, I will give an example. What happens when using posture corsets? Let's say our patient is a stooped person. He has some degree of kyphosis or scoliosis or text neck (due to the "vase" / online lifestyle). In such a patient, some back muscles are stretched and do not function for contractions (impaired motor function), while others are spasmodic (impaired sensory function) and do not relax as they should.
Such a patient puts on a corset on the recommendations of a "doctor" - an orthopedist. He tightens the straps, the shoulders go back, the person visually straightens up and does his business lives his life 
. And everything will be relatively ok while the person is in this corset. Problems will begin as soon as he takes it off.
As someone has already guessed, from the point of view of biomechanics, such a corset will be a bad artificial alternative to some of the patient's muscles. Moreover, these alternative "muscles" will be constantly contracted (tightened belts). But what will happen to the real human muscles?
Those muscles that were stretched and did not contract will stretch even more, because their function was taken over by the corset. Those muscles that were in spasm will relax while wearing the corset, but will immediately spasm even more after you take it off. And I am still roughly describing the bad details of this process, for example, I do not go into the consequences for breathing, because the patient's diaphragm in the corset will not function properly . The situation is similar with shoe insoles, I will not repeat myself, in the post about bad shoes I described the details.
As a result, we get a more unhealthy patient than he was before going to the doctors. It's like immediately prescribing crutches to a person with gangrene. And you'll still pay for it.
In general, such treatment should only be recommended to enemies, so that they die faster.
